In order to get the same keys you will need to replace the lock cylinders on all of the latches you want keyed alike. To do this though, you do need to measure the cylinders themselves in order to get the correct size:
-Replacement Cam Lock Cylinder for RVs - 7/8" Long # 295-000003, 1-1/8" Long # 295-000004, 1-3/8" Long # 295-000005, 1-3/4" Long # 295-000077.
Once you find the correct length (or lengths) you will want to select "Keyed Alike" from the drop-down menu on the product pages... view full answer...
It sure will. With a few exceptions, weight distribution shanks have the same 1-1/4 inch hole spacing. The Curt # C17122 weight distribution shank will work perfectly with the Reese # RP66020 600 lb tongue weight capacity system you referenced. view full answer...